New Zno/Au/Zno Multilayer Field Effect Transistor with Extended Gate as a Sensing Membrane
ZnO/Au/ZnO (ZAuZ) multilayer structures with different thicknesses are deposited on a glass substrate by using the RF and DC magnetron sputtering methods and then are used as extended gates in field effect transistors (FET) for the pH detection. Their structural, optical, and electrical properties are investigated. The thickness parameter affected the pH sensitivity of the multilayers, by increasing the sensitivity from 0.25 мA1/2/pH to 0.3мA1/2/pH in the saturation region and from 50 mV/pH to 66.66 mV/pH in the linear region. On the contrary, in the hysteresis voltage case, it is reduced from 10.11 mV to 9.87 mV, as the thickness of multilayers increases from (100/50/100) nm to (200/100/200) nm.
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